Which size rotary table & chuck style?

[MichaelHenry]

I'm about to order a PCNC 1100 mill and need to decide about 4th axis options.

Tormach offers both 6" and 8" rotary tables and 3-jaw, 4-jaw, or 5C chucks.

I'm inclined to get an 8" RT with a tailstock and 3-jaw chuck. The 6" RT is only 20 lbs lighter so it doesn't seem worthwhile to consider it, but I'm wondering if a 4-jaw chuck might be better than the 3-jaw chuck.

Any thoughts?

Mike

[dave6]

I just took delivery of my Tormach mill and I think I will be ordering the 8" rotory table and 4 jaw to go with it, the tail stock is not a big priorety for me at this time. I guess ultimately the 3 jaw for round stuff and the 4 jaw for everything else. As far as I know you cant hold anything but round stuff in a 3 jaw but a 4 jaw you can put anything in it if you want to dial it out. Just my thoughts. Oh by the way I take back everything I said about making your own stand for the machine, there is no way you can build as nice a stand as they sell for the same price.

[Willyb]

Hi Guys

With the Tormach Rotary Table, how is the 3 Jaw Chuck attached? Thanks for your help with my question.

Willy

[kerryveenstra]

Hi Mike,

> I'm inclined to get an 8" RT with a tailstock and 3-jaw chuck.

That's what I did. I can get a 4-jaw chuck later, and a 3-jaw chuck is fine for what I'm doing now. Compared to the 6" RT, I want to have the extra capability that the 8" RT provides, just in case. (I justify a lot of tool decisions with that reasoning. I even include it in the budget. ;-)

Kerry

[philbur]

I made an 8" adapter plate. Bolt the chuck to the plate then bolt the plate to the rotary table. I made the plate to take either a 6" 4 jaw independent or a 5" 3 jaw self centering.

Phil

Originally Posted by Willyb Hi Guys With the Tormach Rotary Table, how is the 3 Jaw Chuck attached? Thanks for your help with my question. Willy

[digits]

Originally Posted by philbur I made an 8" adapter plate. Bolt the chuck to the plate then bolt the plate to the rotary table. I made the plate to take either a 6" 4 jaw independent or a 5" 3 jaw self centering. Phil

I've just made a similiar if smaller adaptor plate for a 6" RT. I haven't used it in anger yet, but how do you get the chuck aligned with the axis of the RT?

My plan was to bolt the chuck to the plate which will be fairly close to centred, and then loosely bolt the plate to the RT and spin it, while indicating against the edge of the chuck and shifting the plate according to the reading. My theory is that once the indicator reading is constant, the chuck will be aligned with the axis of the RT, even if the mounting plate isn't.

[philbur]

Exactly. But better still (if applicable to the operation) mount the workpiece in the chuck and indicate off the workpiece.

Regards
Phil

Originally Posted by digits My plan was to bolt the chuck to the plate which will be fairly close to centred, and then loosely bolt the plate to the RT and spin it, while indicating against the edge of the chuck and shifting the plate according to the reading. My theory is that once the indicator reading is constant, the chuck will be aligned with the axis of the RT, even if the mounting plate isn't.

[Don Clement]

I mounted a 5C chuck on a 6" RT using tooling plate. The ring with 4 set screws allows the 5C chuck to be adjusted for concentricity. TIR was <0.0005”.

http://i72.photobucket.com/albums/i1...CadapterRT.jpg

Don Clement
Running Springs, California